Unlikely — Zone Mismatch
malanga (zones 9-12) does not overlap with Rhode Island's zone range (6b-7b). Growing outdoors is unlikely without significant protection.
2 zones short — what would close it
Malanga is hardy to zone 9, and the warmest ground in Rhode Island is zone 7 — 2 zones short. Planted in open ground it will not survive a Rhode Island winter. To grow it here, grow malanga under glass — a greenhouse is the only lift this wide the engine models.
A greenhouse is the lift this needs. How a greenhouse changes what you can grow →
Zone math from 9-12 (plant) against 6-7 (Rhode Island). Lift modeled by crop_engine Sprint 20B effective_zone_modifier (+2 zones) via api/fast_sections.py Unlock Engine v2.
Your yard isn't the whole zone.
Rhode Island spans zones 6b-7b, but your yard has its own microclimate — slope, trees, and low spots shift frost and sun across a single parcel. Enter your address and we'll score malanga against your land's actual soil, sun, and frost.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Zone Comparison
Malanga Needs
- USDA Zones: 9-12
- Frost-Free Days: 120+
- Sun: Full Sun
- Mature size: 5 ft tall
- Picking window: ~30 days of harvest
- Drought tolerance: Low
Rhode Island Has
- USDA Zones: 6b-7b
- Last Hard Freeze (28°F): Mar 27 - Apr 3
- First Hard Freeze (28°F): Nov 7 - Nov 21
- Annual Rainfall: 44-52 inches
- Common Soils: Glacial till, Sandy loam, Coastal sand
Plant Zone Range (zones 9-12)
Preferred Soil pH
Plant data: USDA PLANTS Database / Growable Ground plant catalog. State data: USDA ARS PHZM 2023, NOAA Climate Normals, NRCS SSURGO.
When to Plant Malanga in Rhode Island
The frost window
Across Rhode Island, the last spring hard freeze (28°F) clears between Mar 27 and Apr 3, and the first fall hard freeze lands between Nov 7 and Nov 21 (NOAA Regional Climate Centers ACIS, 1991-2020). Counting from the latest last freeze to the earliest first freeze, that's a 218-day window you can count on — up to 239 days on a mild site in a kind year. That marks the hard freeze, not the last light frost, so tender transplants usually wait another 2-3 weeks.
Frost tenderness
Malanga is frost-tender — its listed minimum temperature is 50°F (USDA PLANTS Database) — so set plants out two to three weeks PAST your local last hard freeze, not on it and not on the state's earliest date. The 28°F marker above is when killing freezes stop, not when light frost does.
Days to maturity vs. the window
At 270 days to maturity (USDA PLANTS Database), even Rhode Island's kindest 239-day season runs short — challenging without season extension. An indoor start plus row cover on both shoulders of the season closes the gap.
Frost window: NOAA Climate Normals 1991-2020. Plant timing fields: USDA PLANTS Database. Your site's own frost dates can run earlier or later than the state range — a parcel report pins them down.
Growing Season Fit
The zone check says malanga does not survive a Rhode Island winter in the ground. The season figures below measure a different question — whether it could finish a season here at all — and they only bear on Rhode Island under protection.
Frost-free days
Malanga wants 120+ frost-free days; a typical Rhode Island site sees ~225 (NOAA Regional Climate Centers ACIS, 1991-2020). That leaves comfortable headroom for succession planting.
Growing degree days
Malanga needs ~4000 GDD (base 50°F) to ripen. The state median runs ~2635 GDD (from PRISM 1991-2020 climate normals), so Rhode Island's typical season runs short on heat — pick a south-facing site and consider season extension.
GDD and chill-hour figures are computed from PRISM 1991-2020 monthly climate normals; frost-free days from NOAA Regional Climate Centers ACIS, 1991-2020. Each is the state median across its counties (P25/P75 span the within-state spread). Hardiness-zone range is USDA PHZM 2023.
Soil + Drainage Fit
Malanga tolerates a wide pH range (pH 4.5-7.8) — 3.3 units, acid ground through alkaline — so soil acidity is rarely what limits it in Rhode Island. A soil test is still worth having, but for what else it tells you about this site, not to clear this plant. It will grow across that whole span, but it does best between pH 5.5 and 7 — worth knowing before you decide whether a Rhode Island soil test result is a problem or just a number. Drainage matters: this plant wants well (dry spells). If your Rhode Island site is heavier clay or sits in a low spot, raised beds or amendment with compost solve it.
Your land, not the state average
Rhode Island's soils run mostly fine sandy loam, but SSURGO maps the series, texture, and drainage under your exact parcel. Malanga needs about 19 inches of workable depth, so it is that horizon — not the surface — you are testing for. That map unit, not the state average, decides how malanga performs.
Check your parcel → Source: USDA NRCS SSURGO.
Plant pH and drainage requirements from USDA PLANTS Database. Rhode Island soil profile from USDA NRCS SSURGO. Site-specific verification: a 30-minute soil test from your local Extension lab.
Malanga in Rhode Island — Quick Answer
- Verdict: Unlikely — Zone Mismatch
- Plant Zones: 9-12 (USDA PLANTS Database)
- State Zones: 6b-7b (USDA ARS PHZM 2023)
- Growing Season: 28°F hard freezes about Mar 27 - Apr 3 to Nov 7 - Nov 21 (NOAA Regional Climate Centers ACIS, 1991-2020)
- Days to Maturity: 270 days
What Else to Consider for Malanga in Rhode Island
Zone compatibility tells you about winter cold survival — but Rhode Island growers also need to think about:
Small lot sizes limit garden space in much of the state
Salt spray affects coastal plantings
Rocky glacial soils need clearing
Growing malanga here specifically
Malanga takes ~270 days and rates to zones 9–12; against Rhode Island's ~225 frost-free days, timing is everything.
Buy malanga weeks with an early indoor sowing and season-extending covers. How to handle it →
What to actually do about these — and the constraints that apply to every Rhode Island grower, not just malanga — is covered on the Rhode Island growing guide.
Timing shifts within Rhode Island
Malanga needs about 120 days of frost-free season to complete its cycle. Even Providence County — Rhode Island’s shortest season at 210 frost-free days — clears that by 90 days, so season length isn’t the constraint anywhere in Rhode Island. What varies is your own parcel.
County last-freeze dates and frost-free day counts: NOAA Regional Climate Centers ACIS (1991-2020), county 28°F freeze (earlier than the folk 32°F "last frost"). Malanga's 120-day requirement: USDA PLANTS / Growable Ground plant database (minimum frost-free days). A parcel report resolves your address's own frost dates.
Good to Know Before You Plant Malanga
Malanga is listed as toxic to dogs, cats (all) at a moderate level (ASPCA). Most listed plants only cause brief upset — a raised bed or a fenced corner usually keeps curious pets clear. Worth knowing for placement: in Rhode Island this is a one-season plant and the first hard freeze (Nov 7 - Nov 21) takes it down, so the exposure above is a summer-long one rather than something standing in the bed all year.
Rhode Island Cooperative Extension
For Rhode Island-specific cultivar recommendations, planting calendars, and pest pressure for malanga, the canonical source is URI Cooperative Extension. Their fact sheets carry the local trial data we can't generalize across 50 states.
Is Malanga native to Rhode Island?
No — the USDA PLANTS Database lists Malanga as introduced rather than native in the Lower 48, so it is not part of Rhode Island's native flora. It grows here as a garden plant; pairing it with a few Rhode Island natives keeps local pollinators fed too.
Looking for plants that belong here? The Rhode Island growing guide lists USDA-documented natives for the state.
Native-range data: USDA PLANTS Database state-distribution records, accessed 2026-07-01.
Common Questions About Growing Malanga in Rhode Island
When can I plant Malanga in Rhode Island?
Rhode Island's last spring hard freeze (28°F) clears between Mar 27 and Apr 3, and the first fall hard freeze lands between Nov 7 and Nov 21 (NOAA Regional Climate Centers ACIS, 1991-2020). Malanga is frost-tender — its listed minimum temperature is 50°F (USDA PLANTS Database) — so wait two to three weeks past your site's last hard freeze, when light frost has also stopped, before planting out.
Can Malanga mature before first frost in Rhode Island?
Malanga needs 270 days to mature (USDA PLANTS Database), and even Rhode Island's longest typical season runs 239 days (NOAA Regional Climate Centers ACIS, 1991-2020) — challenging without season extension. An indoor start plus row cover on both season shoulders closes the gap.
What hardiness zone is Malanga grown in across Rhode Island?
Rhode Island spans USDA hardiness zones 6b-7b (USDA ARS PHZM 2023). Malanga carries a range of zones 9-12, so the overlap zones are where outdoor growing is most reliable.
How many frost-free days does a typical Rhode Island site have?
A typical Rhode Island site sees ~225 frost-free days per year (derived from NOAA Regional Climate Centers ACIS, 1991-2020). Malanga needs 120+ frost-free days, so check whether your local microclimate runs above or below the state average before settling on a planting date.
Is Malanga native to Rhode Island?
No — the USDA PLANTS Database lists Malanga as introduced rather than native in the Lower 48, so it is not part of Rhode Island's native flora. It grows here as a garden plant; pairing it with a few Rhode Island natives keeps local pollinators fed too.
How should I amend the soil for Malanga in Rhode Island?
Malanga tolerates pH 4.5-7.8 and well (dry spells) drainage (FAO ECOCROP). That is a 3.3-unit span, acid ground through alkaline, so pH is rarely what limits this plant on a Rhode Island site — amend for drainage and organic matter first.
Will Malanga actually grow on my specific land in Rhode Island?
State-level zone + climate data is a sketch. A Growable Ground parcel report scores malanga against your address's exact soil pH, drainage, sun, and frost-date data drawn from USDA SSURGO, NOAA, and PRISM — not state averages.
Check your specific parcel in Rhode Island
State-level data is a sketch. Your Growable Ground report scores malanga against your parcel's exact soil, sun, drainage, and frost data — not zone averages.
Three things about your lot that Rhode Island malanga averages can't show:
We read public map data around Rhode Island — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Rhode Island malanga average
Explore More
Growing guides for malanga
Analysis by the Growable Ground research team, grounded in USDA PLANTS, USDA NRCS SSURGO, NOAA Climate Normals (1991-2020), and named Cooperative Extension sources. How we know →
Cite this dataset
Kirchick, M. (2026). Growable Ground Plant Database [Data set]. Zenodo. https://doi.org/10.5281/zenodo.21435643
Licensed CC BY-NC 4.0. DOI 10.5281/zenodo.21435643
Last updated: